Exercise 10: CALCULATING DIMINISHING SIZE IN PERSPECTIVE

When you need to create a series of shapes of equal size that must recede in space, it is necessary to have a way to make sure that the shapes are consistent and do not vary in size. In the following example, I have drawn the side of a building at an angle to our point of view.

Create a sequence of windows on the side of the structure by following the steps below.

#1 - Draw a horizontal line from the upper near corner of the building parallel with the horizon line.

#2 - Locate evenly spaced points along the line-in this case I set the spacing at one inch intervals. To create five windows you must indicate ten points on the line.

#3 - Connect each point on the top parallel line with a vanishing point on the horizon.

#4 - At the point where the first two converging lines intersect the lines that are drawn to indicate the top and bottom edges of the windows, draw a heavier connecting line to form the top of the first window. Erasing away the line between the next two points will create the open space or solid wall between the first and second window.

#5 - Complete the windows by drawing vertical lines down to the lower converging line that is placed to indicate the bottom of each window and repeat the process.

#6 - Adding a roof with a peak is a matter of drawing intersecting lines from each corner of the wall to find the center of the square. Draw a vertical line up from the center point to a arbitrary point in space. Connect this new point with diagonal lines to each of the two upper corners of the wall and you have a peak.Variations of this process can be used to create various structures including just about anything you can dream up.

CALCULATING DIMINISHING SIZE IN PERSPECTIVE

Demonstration

Here is another technique for showing diminishing planes as they recede in space. Once again I have created a horizon line and established a vanishing point. I then proceed with the following steps;

#1 - Draw a square in perspective using your vanishing point. Draw diagonal lines from each of the four corners to establish the center point. Draw a line through this center point to the vanishing point.

#2 - Draw a line from the bottom left corner through the point where the center line crosses the right side of the square. Continue this line up to the top converging line.This gives you the upper right corner of the next square.

#3 - Draw a vertical line down from the upper right corner of the next square to the bottom convergence line. You now have the next square completed.

#4 - Continue this sequence as may times as needed until you have drawn the entire structure.